#include <iostream>
using namespace std;
class Date{
    friend class Time;
    int y,m,d;
public:
    Date(int year=0,int month=0,int day=0){
        y=year;
        m=month;
        d=day;
    }
    void display(){
        cout<<y<<"/"<<m<<"/"<<d<<endl;
    }
};

class Time{
    int h,m,s;
public:
    Time(int hour=0,int minutes=0,int seconds=0){
        h=hour;
        m=minutes;
        s=seconds;
    }
    void display(Date& date){
        date.display();
        cout<<h<<":"<<m<<":"<<s<<endl;
    }
};

int main(){
    Date d(2023, 10, 5);
    Time t(12, 30, 45);
    t.display(d);
    return 0;
}